Motorized torch for cutting structural members



3,450,398 MOTORIZED TORCH FOR CUTTING STRUCTURAL MEMBERS Filed July 7, 1967 June 17,1969 1.. E BARNES ET AL Sheet LEWYN E. BAR BY PAUL F. STRU um. 37?? No. 8

June '17, 1969 1.. a. BARNES ET AL 1 v3,450,393

' j MOTORIZED TORCH FOR CUTTING STRUCTURAL MEMBERS Filed July], 1967 Sheeti or e INVENTQRS LEWYN E. BARNES PAUL F. ST RLJBLE I June 17, 1969 L. E. BARNES ET AL 3,450,398,

MOTORIZED TORCH FOR CUTTING STRUCTURAL MEMBERS Filed July 7, 1967 Sheet 3 of e INVENTORS 48 38 LEWYN E. BARNES BYPAUL f: STRUBLE June 17, 1969 E. BARNES ET AL MOTORIZED TORCH FOR CUTTING STRUCTURAL MEMBERS 4 ore Sheet Filed July 7. 1967 FIG. 7

FIG. 9

FIG. 8

June 17, 1969 1.. E. BARNES ET AL MOTORIZED TORCH FOR CUTTING STRUCTURAL MEMBERS Filed July 7, 1967 Sheet INVENTOR FIG. l0 LEWYN E. BARNE BY PAUL F STRUBL June 17, 1969 L. E. BARNES E AL 3,450,398 I MQ'IORIZED TORCH FOR CUTTING STRUCTURAL MEMBERS Filed July 7, 1967 Sheet 6 of s FIG, I? Q INVENTO S Z LEWYN E. BARNES I 12 PAUL F. STRUBLE I I flHHHlHHHHHHIIHIIHHHT" FIG. I8 I United States Patent US. Cl. 266-43 16 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to an oxy-acetylene torch connected to a motor-driven lead screw for movement in a direction normal to the nozzle axis. This torch and lead screw subassembly is connected to a rail-forming base member by means of an adjustable carriage mechanism that enables the torch to be positioned horizontally and laterally relative to the workpiece as well as into position to make vertical cuts along either side thereof. Springwound cable reels mounted on the base member carry connectors that enable the unit to be fastened directly to any workpiece of the type it is designed to cut. Provision is also made on the base member for fastening same to the workpiece so that angle cuts can be made in the latter. The tool holder for the torch provides for adjusting the nozzle tip relative to the surface of the workpiece and also for releasing same from the lead screw so it can be located at any point therealong. The connector on the carriage that allows the torch lead screw subassembly to swing from a horizontal into a vertical position includes detent-stops for orienting it in these relative positions.

Self-propelled cutting torches are, of course, well-known in the prior art for use in cutting plates and sheet metal stock. It is even probable that such units exist for cutting bar stock and even structural shapes to length; however, such units are more than likely fixed in one position and designed to handle only one particular type of material which must be moved to the machine rather than the other way around. Herein lies the prime advantage of the instant unit, namely, it is completely portable and can be moved from workpiece to workpiece at the option of the user. Obviously, it is considerably easier and more efiicient to carry the workpiece than to lift and carefully reposition a structural shape that may weigh several tons for each cut.

The design and versatility of the unit are such that it can accommodate any of the common structural steel members regardless of shape or size. The cuts made are straight and considerably more accurate than could possibly be accomplished with a handheld oxyacetylene torch. The cutting rate is uniform and the nozzle stays a fixed distance away from the surface being cut.

While on the subject of versatility, one extremely important feature of the unit is the fact that it need not be accurately positioned with respect to the structural member when being fastened thereto because provision is made for adjusting the nozzle longitudinally, transversely and rotationally even when so mounted. Therefore, merely fastening the clips carried by the base to the workpiece adjacent the area where the final cut is to be made is sufiicient to permit location of the torch nozzle at the precise place where the cut commences.

A quick-disconnect mechanism associated with the tool holder enables it to be disengaged from the lead screw and reconnected thereto at a different point without having to wait while the motor screws it into its new position. This is of considerable advantage in quickly placing the torch to begin a cut. A double rack and pinion within torch and fasten it onto a particular the tool holder makes it a simple matter to extend and retract the tip of the torch nozzle through a rather extensive range of adjustment.

The torch lead screw subassembly is offset several inches to one side of the base member or bedframe to provide ample room for the torch to operate both vertically and horizontally. It is, of course, essential that the unit be mounted on that portion of the structural shape that is amply supported; otherwise, it would fall to the floor once the unsupported portion became separated. The off set position of the base or bedframe facilitates keeping the unit securely mounted upon the supported portion of the structural member.

It is, therefore, the principal object of the present in vention to provide a novel and improved self-propelled oxy-acetylene torch for use in cutting structural steel members and the like.

A second objective is the provision of a device of the type aforementioned that is completely portable and selfcontained.

Another object of the invention herein disclosed and claimed is to provide a motor-driven lead screw mounting the torch upon a pivoted beam that allows the torch to move vertically and horizontally along with any angle therebetween.

Still another objective is the provision of a unit of the class above-described that incorporates both coarse and fine adjustments by means of which the nozzle of the torch can be accurately located relative to the workpiece.

An additional object is to provide a motorized cutting torch that is suitable for use in cutting any of the common sizes and shapes of structural steel members.

Further objectives of the invention herein disclosed and claimed are to provide a power-operated cutting torch that is relatively inexpensive, lightweight, rugged, easy to operate, versatile, safe, compact and even decorative.

Other objects will be in part apparent and in part pointed out specifically hereinafter in connection with the description of the drawings that follows, and in which:

FIGURE 1 is a top plan view of the motorized cutting torch, portions of which have been broken away to conserve space;

FIGURE 2 is a front elevation, portions of the pivoted beam having been broken away and shown in section to expose the lead screw and drive therefor;

FIGURE 3 is a section taken along line 33 of FIG-v FIGURE 6 is a fragmentary longitudinal section takenalong line 66 of FIGURE 4;

FIGURE 7 is a fragmentary section to an enlarged scale taken along irregular line 77 of FIGURE 1 show-- ing the quick-release connection between the lead screw a and tool holder;

FIGURE 8 is a section URE 7;

FIGURE 9 is a fragmentary side elevation to an enlarged scale, portions of which have been broken away and shown in section to more clearly reveal the internalconstruction of the slips that releasably fasten the unit to the workpiece;

FIGURE 10 is a fragmentary section taken along line 10-10 of FIGURE 3 that shows the adjustable pivot coupling interconnecting the beam and carriage, the tool.

holder having been shown in dotted lines;

FIGURE 11 is a section taken along line 11-11 of FIGURE 10;

taken along line 8- 8 of FIG- FIGURE 12 is a detail showing the notched element of the pivot coupling in side elevation;

FIGURE 13 is a rear elevation showing the notched face of the element of FIGURE 12;

FIGURE 14 is a front elevation of the mating pincarrying element of the pivot coupling;

FIGURE 15 is a side elevation of the element of FIG- URE 14; I FIGURE 16 is a rear elevation of the element of FIG- URES 14 and 15;

FIGURE 17 is a vertical section to an enlarged scale taken along line 1717 of FIGURE 1 showing the double rack and pinion that raises and lowers the tool holder;

FIGURE 18 is a fragmentary vertical elevational view, partly in section, showing the stop dog that locks the carriage to the bedframe; and,

FIGURE 19 is a fragmentary horizontal section showing the toothed stop dog itself. Referring now to the drawings for a detailed description of the present invention and, initially, to FIGURES l, 2 and 3 for this purpose, reference numeral 10 has been employed to broadly designate the bedframe which will be seen to have a hollow generally rectangular cross section although made up of several different elements. Opposite ends of the bedframe are open while the front and rear faces are formed by inwardly-opening channelshaped members 12 and 14, respectively. The upper flanges 16 of each channel are longer than their lower counterparts and they are spanned by an elongate railforming plate 18 with spacers 20 therebetween as shown most clearly in FIGURE 3. The front and rear parallel edges 22 and 24 of the rail-forming plate are beveled both top and bottom to produce a surface better adapted to engage the V-shaped groove 26 in the wheels 28 of the carriage that has been broadly designated by numeral 30 and which runs therealong.

Mounted in the opposite ends of the bedframe are a pair of slideblock subassemblies which have been broadly designated 32R and 32L and which are most clearly revealed in FIGURES 3, 4, and 6' to which reference will now be made. For the most part, these two subassemblies are identical and like reference characters will be employed to designate common parts; however, in the few particulars in which they differ, the letters R and L will be added to dilferentiate therebetween. The right-hand subassembly 32R includes a generally rectangular base plate 34R while the left-hand one (32L) has a speciallyshaped base plate 34L that includes a projecting portion which will be described in detail presently. Both base plates have large cable openings 36 therethrough and each slides between the lower flanges 38 of the channel-shaped members 12 and 14 on slideblocks 40 attached to their front and rear margins.

Sideplates 42 rest atop the slideblocks 40 and are attached thereto permanently. These sideplates extend between the two slideblocks on the same inside face of the bedframe and are sized to fit within the channels formed by members 12 and 14. Guideblocks 44 on the top margins of the sideplates move along the underside of upper flanges 16 and cooperate with the slideblocks 40 to maintain the sideplates in slightly-spaced parallel relation to the vertical webs of the channel members 12 and 14.

Reel shaft 46 is mounted non-rotatably between the sideplates 42 over cable opening 36 in the base plates 34R and 34L. Cylindrical reel body 48 mounts on shaft 46 for relative rotation and helical spring 50 operatively interconnects the two biasing the former element toward the wound condition. Cable 52 is wound around the reel'several turns and has one end dead-ended thereon while the free end carries the adjustable clips that have been broadly designated by reference numeral 54 and which will be described in detail presently in connection with FIGURES 3 and 9 where they are most clearly revealed. For the present, it is suflicient to note that these clips 54 hook beneath the flanges of the workpiece W as shown in FIGURE 2 with the spring-wound reels continuously-biasing them into tight engagement therewith. When the cable is fully wound onto the reel, the clips can be located on the cable such that said cable will have to be partially unwound and the spring tensioned before the clips can be hooked onto the workpiece. This insures that'the entire unit will be securely fastened to the workpiece and, obviously, the adjustable feature by which the clips can be fastened to the cable at any point makes it possible to accommodate workpiece flanges of various sizes. The slideblock subassemblies 32R and 32L are moved toward or away from one another as necessary to accommodate .the width of a particular workpiece as is also clearly revealed in FIGURE 2. Under most circumstances, slideblock subassembly 32L can be left in fixed position adjacent one end of the bedframe 10 while slideblock subassembly 32R is adjusted relative thereto; however, provision is made for adjusting both of them should the need arise.

Now, before leaving the slideblock subassemblies, the differences in subassembly 32L will be noted in connection with FIGURES 4, 5 and 6. Bedplate 34L is provided with a pivot pin 56 located on the longitudinal centerline of the bedframe adjacent cable opening 36 as shown in FIGURE 4. Mounted upon pivot pin 56 underneath the bed-frame for pivotal movement relative thereto is a mitering protractor 58 that carries an angular scale 60 bordering an arcuate slot 62 within which wingnut type fastener 64 slides for fastening same in adjusted position to the projecting portion 66 of the bedplate 34L This projecting portion 66 of the bedplate carries fastener 64 radiallyspaced from pivot 56 along the longitudinal centerline of the bedframe 10 as seen quite clearly in FIGURE 4. Adjacent fastener 64 is an index mark 70 locating the longitudinal centerline of the bedframe which, upon movement along scale 60, indicates the degree of angularity the bedframe occupies relative to the workpiece in much the same manner as a mitering protractor used on a table saw, The downturned fence-forming ears 72 on the inside margin of the protractor 58 extend downward perpendicularly when the bedplate is horizontal and also lie normal to the longitudinal centerline thereof in position to engage a vertically-disposed surface of the workpiece and orient the bedframe relative thereto as in FIGURE 2. The gap 74 (FIGURE 5) left between the flanges 72 receives the clip 54 therebetween. A notch 76 in the protractor 58 registering with the opening 36 in the bedplate 34L passes the self-winding reel cable 52. The above-described structure allows the unit to be precisely mounted on the workpiece at any desired angularity relative thereto for the purpose of making both squarerand mitered cuts. The clips 54 can, of course, twist the cable 52 the quarter turn or so necessary to fasten same to the workpiece flanges.

Next, with reference to FIGURES 3 and 9, the details of the clip construction will be set forth. Both clips 54 are identical and they include a generally J-shaped book 78 fastened to the closed end of buckle member 80. The buckle member, in the particular form shown, has a pair of spaced parallel sideplates 82 interconnected across one end by cable guide 84 that includes a vertically-disposed cable opening 86 therethrough that intersects a transversely extending cylindrically-surfaced cam-receiving groove 88. A cam member 90 similar to that of a seat belt buckle is mounted for pivoial movement between the sideplates 82 on eccentric pivot pin 92. The cam surface 94 of cam member 90 that moves within cam groove 88 in the cable guide is curved about essentially the same center as said groove although the radius of curvature is less by approximately the diameter of the cable. The eccentric mounting of the cam member causes it to close gap 96 and squeeze the exposed portion of cable between the cam surface 94 and the surface of cam-receiving groove 88 upon the application of a force in the direction to wind cable 52 back on reel 48 such as is constantl exerted by spring 50.

Now, with reference to FIGURES 1, 2, 3, -16, 18 and 19, the carriage subassembly 30 will be set forth in detail. A baseplate 98 carries V-grooved wheels 100 journaled on shafts 102 located on all four corners. Wheels 100- run along the bevel-edged tracks 24 formed on opposite side margins of plate 18. The bedplate 98 as thus supported is free to roll from end to end of the bedframe 10.

With particular reference to FIGURES 1, 3, 18 and 19, it will be noted that the bedframe 10 carries a toothed rack 104 adjacent the top edge of channel member 14 extending the entire length thereof. A boss 106 (FIGURE 18) formed in bedplate 98 receives the spaced parallel pins 108 of latch member 110 for vertical reciprocating movement alongside the rack 104. A short toothed rack section 112 is attached to the lower extremities of the pins 108 adapted to interlock with said rack 104 when the locking member is dropped into engaged position. Raising the locking member into the position shown in FIGURE 18 disengages short rack 112 from long rack 104 and enables the carriage to be moved to any selected position along the bedframe 10.

In FIGURES 1, 3 and 10, it will be noted that a housing 114 rests atop the bedplate 98 and it contains a pair of spaced parallel bores 116 and 118 whose axes extend horizontally and normal to the direction of carriage movement. Annular enlargements in opposite ends of these bores receive sleeve bearings 120 that journal spindle 122 and guidepin 124 for reciprocating movement within bores 116 and 118, respectively. Spindle 122 includes a keyway 126 milled in the side thereof that opens onto an intersecting vertical bore 128 in the housing. Keyway 126 contains a rack 130 that mates with pinion 132 on the lower end of shaft 134 that is journaled for rotation inside the vertical bore and which includes an operating knob 136 atop the housing. Rotation of knob 136, of course, causes spindle 122 to reciprocate inside housing 114. A collar 138 is attached nonrotatably on the rear extremity of the spindle by means of pins 140. Projecting from this collar is an integrally-formed elbow 142 containing a forwardlyfacing socket positioned to receive the rear extremity of guidepin 124 to which it is attached by pin 144. Thus, the collar and elbow cooperate to form a connector bridging the spindle and guidepin so that they reciprocate as a unit and the latter prevents the former from rotating in the housing.

Referring for the moment to FIGURE 10, it will be noted that spindle 122 has an axial bore 146 therethrough with a threaded section 148 at its rear extremity which is separated from the smooth section thereof by a shoulder 150, A push-rod 152 having a head 154 on its rear end is mounted in the bore 146 for free sliding movement, the head 154 limiting the forward thrust thereof by striking shoulder 150. A threaded plug 156 screwed into the threaded portion 148 and a compression spring 158 abutting the adjacent extremities of said plug and pushrod cooperate to bias the latter forwardly.

A rearwardly-facing shoulder 160 near the front end of the spindle 122 engages the front sleeve bearing 120 in bore 116 and limits the extent to which the spindle can be retracted by the rack and pinion. The forwardmost extremity of the spindle carries an annular flange 162 against which the inner race of roller bearing 164 abuts, the latter being mounted on the spindle with a press fit. The outer race of this roller bearing is similarly fastened inside cup-shaped element 166 in abutting relation to shoulder 168 provided therein. A ring 170 attached to the rear face of the cup-shaped member 166 engages the corresponding face of the outer race and keeps it in place against shoulder 168. The enclosed end 172 on the front face of the cup-shaped member retains the elements of the slip-disk coupling that has been broadly designated by reference numeral 174 and which will be described in detail presently. The hollow rectangular beam subassembly that has been referred to in a general way by reference numeral 176 is bolted or otherwise fastened to the front face of the cup-shaped member 166 as shown. Thus, the mechanism above-described provides the means by which the beam subassembly 176 may be rotated about the horizontal axis defined by spindle 122 and also moved forwardly and rearwardly relative to the bedframe 10. The roller carriage 30 described previously, of course, provides for relative sidewise movement between the beam and bedframe subassemblies.

Attention is now specifically directed to FIGURES 10- 16, inclusive, for description of the slip-disk coupling 174 that is employed to releasably latch the beam subassembly in either vertical or horizontal position. The nonrotating element of the coupling is seen in FIGURES 14, 15 and 16 to comprise a fiat circular disk 178 sized to fit inside cup-shaped element 166 with room to reciprocate forwardly and rearwardly therein. From the rear face of disk 178 projects a center pin 180 adapted to reciprocate back and forth within the axial bore 146 in the spindle 122 in abutting relation to the front end of the push-rod which continually urges same forwardly. On opposite sides of center pin 180 are a pair of eccentrically-located pilot pins 182 whose axes lie in spaced parallel relation to one another and to said center pin. These pilot pins reciprocate in drilled sockets 184 provided in the ends of the spindle alongside axial bore 146 and in spaced parallel relation thereto. Pins 182 coact with the spindle to prevent disk 178 from rotating while permitting a limited amount of relative axial motion.

The front face of disk 178 contains a horizontal semicylindrical groove 1-86 and a vertical semi-cylindrical groove 188, both of which are also diametrical. Fastened Within these grooves are cylindrical pins and 192 that each present a forwardly-projecting semi-cylindrical detent which, as will be seen presently, releasably latch within corresponding V-shaped grooves 194 and 196 in the rear face of the rotatable disk element 198.

Disk 198, in the particular form illustrated, is approximately the same diameter and thickness as disk 178 which it mates with in face-to-face relation. Diametrical V-shaped grooves 194 and 196 intersect one another at right angles and are of a width and depth adapted to releasably receive the projecting portions of pins 190 and 192. The front face of rotatable disk 198 also has a pair of eccentrically-located pins 200 that fit into corresponding holes 202 in the closed end 172 of the cup-shaped member 166.

Thus, rotatable disk 198 rotates with the cup-shaped member 166 and the beam subassembly 176; whereas, the non-rotating disk 178 merely reciprocates relative to the spindle. In FIGURE 10, the beam subassembly 176 is shown latched in horizontal position as is the case in FIGURES 1, 2 and 3. To maintain this position, spring 158 biases push-rod 152 forwardly against pin 180 which, in turn, urges disk 178 against disk 198 so that the pins 190 and 192 find their way into one of the two V-shaped grooves 194 and 196. At such time as it becomes necessary to swing the beam subassembly into vertical position for making a vertical cut, the operator merely turns the beam to the new position because pins 190 and 192 will ride up the sloping sides of the V-shaped grooves onto the planar face of disk 198 thereby depressing disk 178, the push-rod and pilot pins against the bias imposed on this subassembly by spring 158. Once the beam reaches vertical position, pins 190 and 192 will, of course, be biased into the other of the two V-shaped grooves to maintain this position.

The beam subassembly 176 is most clearly revealed in FIGURES 1-3, 7, 8 and 10 to which specific reference will now be made. The beam itself 204 is elongate, hollow and essentially square in cross section having front and rear walls 206 and 208,.respectively, a top 210. and a bottom 212. The right end is closed by a cap 214 and the left end by a bearing block 216 that mounts a bearing 218 in which the lead screw 220 is journalled for rotation. A

second bearing block 222 (FIGURE 2) similar to hearing block 216 is spaced inwardly from the right end cap 214 and journals the other end of the lead screw 220 while, at the same time, cooperating with cap 214 to produce a motor compartment 224. Housed within this motor compartment is the reversible lead screw drive which includes a reversible electric motor 226, a speed reducer 228 and a coupling 230, operatively interconnecting said drive mechanism and the lead screw 220. The motor is, of course, connected to a source of electric power (not shown) and suitable switches are provided accessible to the operator for starting, stopping and reversing same.

Next, with specific reference to FIGURES 3, 7, 8 and 10, the traveling block subassembly that has been broadly referred to by reference numeral 232 will be set forth in detail. A hollow cast block 234 having an irregularlyshaped longitudinal opening 236 extending between the ends thereof in position to pass the lead screw 220 therethrough loosely fits inside the beam as shown most clearly in FIGURE 8. Right angle grooves 238 extend longitudinally along all four edges and each of these grooves has a guideblock 240 with a square cross-section mounted in opposite ends thereof that run along the inside corners of the beam as shown. The top face of the block has a longitudinal groove 242 therein centered between the side margins and lying directly underneath the central slot 244 in the top wall 210 of the beam. The latter groove receives mounting flange 246 of the tool holder which is generally identified by reference numeral 248 and to which specific reference will be made presently.

The operative connection between the traveling block subassembly and the lead screw 220 is made by means of a pair of spreadable jaw elements 250 that are mounted Within inner vertical groove 252 on the left hand end of the block for pivotal movement on pins 254. The jaws 256 of the jaw elements 250 comprise internally-threaded tubular segments disposed on the lower extremities of upwardly extending arms 258, the pins 254 being located in the upper ends thereof in side-by-side spaced parallel relation to one another and anchored in the left face of the block as shown mostly clearly in FIGURE 7. Thus, when the jaws swing apart, they will disengage from the lead screw and enable the traveling block subassembly to be moved along the beam to any desired location thereon.

The jaws are moved between their engaged and disengaged positions by a jaw-actuating member 260 that is mounted for vertical sliding movement in middle vertical groove 262 formed in the left hand end of the block 234. Groove 262 is slightly wider than inner groove 252 so as to provide a shoulder 264 (FIGURE therebetween against which the jaw-actuator rests.

The jaw-actuator comprises an inverted generally U- shaped member guided for vertical movement between the side edges of groove 262 as shown in FIGURE 8. The opening between the legs of the U pass the lead screw. A pair of pins 266 project to the right from the inner face of the jaw-actuator into upwardly and inwardly inclined slots 268 provided in the arms 258 of the jaw elements below pivot pins 254. Thus, it will be seen that as the jaw-actuator is raised up from the position shown in FIG- URE 8, pins 266 riding in slots 268 will cause the jaws to move apart and disengage themselves from the lead screw. An operating handle 270 projects upwardly from the top of the actuator into the top of the beam through central slot 244 therein. 7 v

The jaw member 250 and actuator therefor 260 are held in place within their respective grooves 252 and 262 by a coverplate 272. This coverplate fits into an outer vertical groove 274 in the left face of the block that is still wider than the middle groove 262 so as to provide another shoulder 276 for it to rest :against. The vertically disposed portion 278 (FIGURE 8) of the coverplate has a notch 280 along the bottom edge thereof sized to pass the lead screw. Coverplate 272 also includes an overhanging flange 282 that overlies the top edge of the jawactuator 260 and includes a slot 284 adapted to pass the operating handle 270 thereof. A compression spring 286 on said handle compressed between the underside of the overhanging flange and the top of the actuator normally biases the latter downwardly so as to keep the jaws engaged with the lead screw. The coverplate is removably attached to the left face of the block by suitable fasteners (not shown).

Now, the actuator can, of course, be raised by merely pulling upon operating handle 270; however, in the construction illustrated, :a crank member 288 pivotally mounted on tongue 290 of the tool holder is used for this purpose. The upper extremity of the operating handle has a double head 292 thereon that defines an annular groove 294 into which the bifurcated leg 296 of the crank fits :as shown most clearly in FIGURE 7. Pivot pin 298 extends transversely through tongue 290 of the tool holder in which it rotates and leg 296 is fastened to one end thereof while crank arm 300 is attached to the other. As seen in FIGURES 2 and 7, rocking the crank arm 300 to the right will raise the operating handle 270 in opposition to the bias exerted thereon by spring 286, thus releasing the traveling block subassembly from the lead screw for reengage-ment therewith at a different position.

Finally, with particular reference to FIGURES 1, 2, 3 and 1 7, the details of the tool holder 248 'will be set forth. The tongue 290 referred to previously as the support for crank 288 forms a part of connector 302 that also includes flange 246 which attaches to the traveling block for movement therewith along the lead screw. The front face of this connector element 302 mounts the verticallyelongated box 304 that moves in upright position along the corresponding face of the beam. The front wall 306 of box 304 has a vertical slot 308 therein that passes pinion shaft 310. The inner or rear end of pinion shaft 310 is journaled for rotation within block 312 that slides up and down within the confines of box 304 limited, of course, by the length of slot 308. The block 312 has a pair of grooves 314 and 316 in its right and left faces, respectively, that receive fixed rack 318 mounted upon the right wall of the box and movable rack 320 that moves with the nozzle clamp 322 up and down the left wall 324 within vertical groove 326. Pinion 328 is mounted on the pinion shaft 310 for rotation therewith in transverse slot 330 of the block that interconnects the rack grooves 314 and 316. The teeth of this pinion mesh simultaneously with both racks 318 and 320. From an examination of FIGURE 17, it will be apparent that clockwise rotation of pinion shaft 310 will cause the pinion to climb up fixed rack 318 and, in so doing, double the vertical excursion of rack 320 over that which would be possible if the pinion were fixed and rack 318 eliminated. An operating knob 332 is provided on the outside of the box for use in raising and lowering nozzle clamp 322. Block 312 has a reasonably tight sliding fit within box 304 so that the unit need not be locked in adjusted position.

Clamp 322 grips the nozzle 334 of an oxy-acetylene torch which-is equipped to receive a mixture of both oxygen and acetylene to be used for cutting purposes in the ordinary way. These gases are, of course, supplied from gas bottles (not shown through suitable high pressure hoses.

In conclusion, the usual manner of using the unit will be set forth briefly in connection with FIGURE 2 where the workpiece W has been shown. Assuming an ordinary right angle cut is to be made, the slideblock subassemblies 32R and 32L are moved along the bedframe 10 until they are spaced apart the same width as the workpiece W and the index mark 70 on the bedplate 34L of subassembly 32L is set at 0 on the protractor scale 60 so as to position the :down'turned flanges 72 normal to the beam 204. The clips are then adjusted on cables 52 at less than the depth of the workpiece flanges before unwinding some of the cable and hooking the clips onto the lower flange margins with the cable reel springs tensioned. Next, the carriage 30 is released by disengaging dog 112 from rack 104 so that the pivotal connection 17-4 between the carriage and beam can be moved to a point alongside the workpiece; whereupon, the beam is swung into vertical position with the tip of nozzle facing the flange to be out. Now, actuation of kno'b 136 will move the beam and tool holder 248 along with the nozzle 334 carried thereby in or out until it reaches the precise position selected for the cut. Following this, the tool holder 248 will be disengaged from the lead screw 220 by actuating crank 288 so as to open jaws 256 and repositioned slightly beyond one edge of the workpiece flange which is to be cut first. Thelast step prior to making the cut is to actuate knob 332 and move the nozzle tip to the proper distance away from the workpiece for making the cut. All that remains to "be done is to turn on motor 226 so as to start the lead screw rotating in the direction required to bring the nozzle across the workpiece.

Once this first flange has been cut, the beam is turned into horizontal position, the tool holder relocated on the lead screw at the beginning of the workpiece web and the nozzle run down to the proper distance to commence the web cut. The out is completed as it was begun by again turning the beam into vertical position but with the nozzle on the other side thereof to sever the remaining flange. As the severed end drops off, the unit remains supported on the workpiece.

Having thus described the several useful and novel features of the motorized oxyacetylene torch of the present invent-ion, it will be seen that the many worthwhile o'bjectives for which it was developed have been achieved. Although but a single specific embodiment of the invention has been disclosed herein, we realize that certain changes and modifications therein may well occur to those skilled in the art within the broad teaching hereof; hence, it is our intention that the scope of protection afforded hereby shall be limited only insofar as said limitations are expressly set forth in the appended claims.

What is claimed is:

l. A motorized torch for cutting structural steel beams and the like which comprises: an elongate rigid bedframe of a length adapted to lay across a workpiece adjacent the portion to be severed therefrom; clamping means carried by the bedframe for securing same to the workpiece; a carriage mounted atop the bedframe for adjustable movement in the direction of the length thereof; stop means interconnecting the bedframe and carriage adapted to lock the latter in adjusted position; a pivotal coupling carried by the carriage and projecting horizontally therefrom beyond the bedframe in a direction normal to its length; an elongate hollow beam attached to the coupling for rotational movement in a perpendicular plane spaced to one side of the bedframe in parallel relation thereto, said beam having an elongate slot in the top thereof communicating with the interior; a reversible motor mounted within one end of the beam; 21 jackscre'w journaled for rotation lengthwise inside the beam with one end operatively connected to the motor; a traveling block mounted inside the beam for sliding movement from end-to-end thereof independent of the jackscrew; releasable jaw means carried by the traveling block and movable from an engaged position operatively connecting said block and lead screw for powered movement in response to rotation of the latter and a disengaged position disconnected therefrom; jaw actuator means accessible through the slot in the beam and movable with the traveling block operative upon actuation to shift the releasable jaw means between its engaged and disengaged positions; and, an externally-located tool holder connected through the slot therein to the traveling block for movement therewith, said tool holder carrying a clamp adapted to receive the tubular nozzle of a cutting torch and support same alongside the beam in spaced perpendicular relation to the axis of the lead screw on the opposite side thereof from that occupied by the bedframe.

2. The motorized torch as set forth in claim 1 in which: two independent clamping means are carried by the bedframe, at least one of which is mounted for adjustment longitudinally relative thereto and to the other of said clamping means to vary the spacing therebetween so as to accommodate workpieces of different widths.

3. The motorized torch as set forth in claim 1 in which: the bedframe includes spaced parallel rail-forming means extending lengthwise thereof; and, the carriage is equipped with wheels mounting said carriage for rolling movement along said rail-forming means.

4. The motorized torch as set forth in claim 1 in which: means comprising a rack and pinion interconnect the carriage and pivotal coupling adapted to adjust the latter along its axis of pivotal movement, said rack and pinion being operative upon actuation to shift the beam and tool holder carried thereby horizontally relative to the bedframe so as to position the torch nozzle at the precise position on the workpiece where the cut is to be made.

5. The motorized torch as set forth in claim 1 in which: the pivotal coupling includes a pair of disks mounted in face-to-face relation with one of said disks being fastened to the beam and the other to the carriage, and interlocking groove and detent means carried upon the opposed faces of the disks adapted to releasably latch the beam in vertical and horizontal positions.

6. The motorized torch as set forth in claim 1 in which: the jaw means comprises a pair of arms mounted side-by-side on the traveling block for independent pivotal movement about transversely spaced parallel axes paralleling the lead screw axis, said arms each having an arcuate internally threaded jaw formed thereon remote from the pivot adapted to close upon the lead screw to form a driving connection therewith when in engaged position and to open releasing same when disengaged therefrom.

7. The motorized torch as set forth in claim 1 in which: the tool holder includes a movable rack attached to the clamp and a pinion meshed with the rack operative upon actuation to move the torch carried by said clamp relative to the workpiece.

8. The motorized torch as set forth in claim 2 in which: one of said clamping means includes a fiat plate pivotally attached to the underside of the bedframe for movement in a horizontal plane about a vertical axis, one edge of said plate having a downturned flange projecting beneath the bedframe in position to engage a side of the workpiece and orient said bedframe relative thereto, and said plate having an arcuate slot therein radially spaced from its axis of pivotal movement using the latter as a center; and, in which the bedframe carries a releasable fastener passing through the slot in said plate adapted to lock the.

latter in adjusted position.

9. The motorized torch as set forth in claim 2 in which: both of said clamping means include a self-winding cable reel journaled for rotation on the underside of the bedframe, a cable wound on said reel with one end deadended thereon and the free end hanging therebeneath, and an adjustable hook fastened to the free end of the cable, said hook including releasable means adapted to grip said cable at selected points so as to hook onto the workpiece with said cable under tension and the reel partially unwound.

10. The motorized torch as set forth in claim 3 in which: a rack is attached to the bedframe alongside one of the rail-forming means; and, in which a hand-rotated pinion is carried by the carriage in position to mesh with the rack, said pinion being operative upon rotation to move the carriage along the rail-forming means.

11. The motorized torch as set forth in claim 5 in which: the disk carried by the carriage is mounted thereon for non-rotatable reciprocating movement between an extended position in which the detent means are seated within the groove means and a retracted position wherein 11 the disk fastened to the beam is free to rotate therewith; and, in which the pivotal connection includes a push rod mounted upon the carriage for reciprocating movement behind the reciprocating disk, and a compression spring behind said push rod operative to normally bias said disk toward its extended position.

12. The motorized torch as set forth in claim 5 in which: the groove and detent means comprise horizontally and vertically disposed diametrical bars projecting from the surface of one of said disks and horizontal and vertical V-shaped grooves sized to receive said bars extending diametrically on the other of said disks.

13. The motorized torch as set forth in claim 6 in which: the jaw arms include a pair of downwardly and outwardly divergent slots located between the arcuate jaws and pivots; and, in which the jaw actuator means comprises an inverted generally U-shaped element mounted upon the traveling block for vertical movement in faceto-face relation to the jaw means and with the jackscrew passing therethrough, and a pair of pins projecting from said U-shaped element into the slots in the arms, said pins being operative to spread the jaws apart and release same from the jackscrew when the block is raised.

14. The motorized torch as set forth in claim 7 in which: the tool holder includes a second fixed rack meshed with the pinion on the opposite side thereof from the movable rack, and in which the pinion is mounted for movement along the fixed rack.

15. The motorized torch as set forth in claim 9 in which: at least one slideblock is mounted within the bed frame for movement in the direction of the length thereof; and, in which one of the self-winding cable reels is journaled for rotation Within the slideblock for movement therewith.

16. The motorized torch as set forth in claim 10 in which: the stop means comprises a retractable dog carried by the carriage movable from an extended position in meshed engagement with the rack to a retracted position disengaged from the latter.

References Cited UNITED STATES PATENTS 2,474,153 6/ 1949 Livesay 266-23 FOREIGN PATENTS 1,044,147 6/ 1953 France.

I. SPENCER OVERHOLSER, Primary Examiner.

ROBERT D. BALDWIN, Assistant Examiner. 

